2003 Cadillac sts 4.6 Northstar

My car has 39 k on it and uses a lot of oil. I mean a quart ever two weeks and it does not drive many miles. Less than 150 in that period. What is going on? Just the Northstar engine?? Or is it a bigger priblem. Its still under warrenty.

A quart of oil every 150 miles is excessive. It is under warranty, take it to the dealer for evaluation.

What kind of oil do you use? Do you take it to a place that uses “bulk oil”? What kind of oil filter do you use? Some and I only say some…northstar engines seem to burn synthetic oil more frequently than “dino” oil. A quart of oil per 150 miles is excessive and the engine should be checked.

Check or have the shop check your oil (looking for antifreeze mixed in) and antifreeze (looking for oil mixed in). You can also look at your oil cap to see if there is any foam in the cap. This would indicate you might have an intake manifold gasket leak or possibly intake manifold crack. At the worst, you could have a head gasket problem.

Do you notice any smoke coming out the back like you are burning oil?

I would definitely take it in to have it looked at very soon. Do you have an extended warranty?

no smoke and no foam. Just had a coolent leak fixed with crossover gaskets and a kit for the area by the left front wheel. I do have a extended warrenty thank god!!

When did the excessive oil usage start? Was it about the time you got the gaskets replaced? It might be a poor job replacing the crossover gaskets.

No it was prior. The leaks are fixed but not the oil issue. Put a quart in today and will check the mileage till I put another one in. Thanks

A quart every 150 miles would leave a cloud of blue smoke if you were BURNING it. Are you sure you are not LEAKING it?? The Northstar engine, a Lotus design, has been around since 1993. They have few problems and certainly not high oil consumption. You should start demanding a replacement engine, not a “repair”…